The field of the invention pertains to the supply of electrical power to electric devices and, in particular, to the power cords that connect portable wheeled electric devices to wall sockets in a hospital setting. The power cords typically plug into both the wall sockets and into the backs of the portable devices. In a hospital setting the devices are frequently moved while plugged in and on occasion individuals walk behind the devices. Under such circumstances the power cords inadvertently become loosened and unplugged from the device.
With the advent of micro-computers the hospital devices have become very sophisticated. Lengthy and important tests are performed with the portable devices now employed. With inadvertent unplugging, the entire test can be lost, the device damaged or possibly the health of a patient jeopardized.
U.S. Pat. No. 2,722,665 discloses a safety guard to retain plugs to a wall socket. The guard comprises a slotted shield having flanges that fit behind the cover plate of the wall socket. Thus, the cover plate retains the guard in place and the plugs are trapped between the guard and the socket.
U.S. Pat. No. 3,491,327 discloses a safety cover also having flanges that fit behind the cover plate. This cover also traps the plugs between the cover and socket with the power cords passing out through an aperture in the bottom of the cover.
In U.S. Pat. No. 4,045,108 a spring device is fastened over the plugs and retained in place by the center screw of the socket cover plate. The power cords pass through slots between the resilient legs that retain the plugs.
U.S. Pat. Nos. 4,652,069 and 5,011,427 each disclose two piece adjustable retainers that fasten to the wall socket by the center screw of the socket cover plate. The adjustable retainer comprises a second slotted part that adjusts for the length of the plug along the cord.
As distinguished from the above devices which all are directed to wall sockets, U.S. Pat. No. 5,174,293 discloses a portable medical device rack on wheels with a variety of power cords plugged into the back of devices in the rack. Disclosed are a variety of shaped metal retainers to prevent the power cords from becoming unplugged from the devices. The retainers utilize screws or a variety of mechanical fastening means built into the device cabinet to prevent the retainers and plugs from detachment. Thus, these retainers require the cabinets to be specially equipped for the matching retainers.
Most medical device cabinets do not provide any specific means to attach retainers for the power cords. In addition, with many sophisticated devices the manufacturers' warranty is voided if the cabinet integrity is violated by drilling holes for screws in the cabinet back. Thus, the applicant's new retainer as disclosed below is directed to a universal device that does not violate cabinet integrity.